<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div id="app">
        <input type="text" v-focus1 id='inp'>
    </div>
    <script src="../vue.js"></script>
    <script>
        //inp.focus();//因为定义了id 所以可以不用document.querySelector('#inp');
        new Vue({
            el:'#app',
            directives: {
                focus1:{
                    //钩子函数
                    inserted(el){
                        el.focus();
                    }
                }
            }
        })
    </script>
</body>
</html>